1. Technical Field of the Invention
This invention relates to thermoplastic thermosettable polyamides having enhanced low temperature flexibility and high temperature thermal stability properties. More particularly, this invention relates to modified polyamides that are essentially linear and thermoplastic at temperatures of less than about 250.degree. C. and thermosetable at temperatures of about 250.degree. C. or more (e.g., 260.degree. to 300.degree. C.); such polyamides being useful in the formation of fibers, molded parts, hot melt adhesives, etc. Still more particularly, this invention relates to polyamides modified by the inclusion therein of mixtures of poly(oxytetramethylene) diprimary amines with poly(oxytetramethylene) oligomers containing one or more internal secondary amine groups and terminal primary amine groups.
2. Prior Art
Poly(oxytetramethylene) diprimary amine oligomers containing internal secondary amine groups are disclosed in Schoenieben et al. European Patent No. 0,354,501 dated Jun. 8, 1989.
Nakagawa et al. U.S. Pat. No. 3,558,419 is directed to composite filaments and fibers wherein one of the components is a polyalkylene ether-polyamide-block copolymer containing linear polyamide segments and polyoxyalkylene ether segments. Amine derivatives of polyoxyethylene glycols, when incorporated into polyamides, tend to affect the water solubility characteristics of the resultant polyamides.
In Yeakey et al. U.S. Pat. No. 4,128,525, thermoplastic adhesive components are disclosed which are prepared from a polyoxypropylene polyamine, piperazine and a dicarboxylic acid.
Linear polymeric amines prepared by first propoxylating a poly(oxytetramethylene) glycol and then reductively aminating the adduct are disclosed in Watts, Jr. et al. U.S. Pat. No. 4,181,682.
Rasmussen U.S. Pat. No. 4,218,351 is directed to impact resistant thermoplastic polyamides composed of a short chain polyamide-forming moiety, a polyamide-forming dimer acid moiety and a polyamide-forming oligomer moiety.
Wettable adhesives comprising a mixture of polyvinyl alcohol and a water soluble polyamide are disclosed in Soerens U.S. Pat. No. 4,684,439. The polyamide comprises a reaction product of a polyoxyalkylene polyamine, a saturated aliphatic dicarboxylic acid and a polyalkylene polyamine.
Mitchell et al. U.S. Pat. No. 4,062,820 is directed to hot melt adhesives prepared by the co-condensation of stoichiometric amounts of (a) a mixture of a polymeric fatty acid and a saturated aliphatic dicarboxylic acid with (b) a mixture of a saturated aliphatic diamine with either a polyoxyethylene diamine or a polyoxypropylene diamine.
Resinous polyoxamide thermoplastic adhesive compositions are disclosed in Schulze U.S. Pat. No. 4,119,615 that are prepared by reacting a polyoxypropylene diamine or a polyoxypropylene triamine with oxalic acid or a dialkyl ester of oxalic acid to prepare a liquid prepolymer that is then reacted with a diamine to provide the resinous polyoxamide.
Resinous thermoplastic adhesive compositions are disclosed in Klein U.S. Pat. No. 4,133,803 that are prepared by reacting a polyoxypropylene diamine or a polyoxypropylene triamine, such as ethylene diamine, with an aromatic or aliphatic dicarboxylic acid or an ester or anhydride thereof, such as isophthalic acid, dimethyl terephthalate or phthalic anhydride.
Vogel U.S. Pat. No. 4,151,173 discloses lubricating oil additives prepared by reacting a polyoxyalkylene polyamine, such as a polyoxypropylene diamine or a polyoxypropylene triamine with a carboxylic acid acylating agent such as a polyisobutenyl succinic anhydride.
Thermoplastic adhesive compositions are disclosed in Yeakey et al. U.S. Pat. No. 4,162,931 and Yeakey et al. U.S. Pat. No. 4,182,845 that are prepared by reacting a polyoxypropylene diamine or a polyoxypropylene triamine with piperazine and an aromatic or aliphatic dicarboxylic acid or an ester or anhydride thereof, such as isophthalic acid.
Rieder U.S. Pat. No. 4,239,635 discloses carboxylic acid terminated diamides, and the alkali metal, ammonium and amine salts thereof prepared by reacting an excess of a polyoxyalkylene polyamine, such as a polyoxypropylene diamine with an excess of an organic polycarboxylic acid.
Hot melt adhesive copolyamide compositions are disclosed in Sharkey U.S. Pat. No. 4,282,346 that are prepared by reacting a polyoxypropylene diamine with piperazine and mixture of a long-chain and a short-chain saturated aliphatic dicarboxylic acid such as adipic acid and azelaic acid.
See also, Vol. 18, pp. 328-436 of the Encyclopedia of Chemical Technology, Kirk Othmer, 3rd Edition.
Newbould in an article entitled "Controlling Melt Viscosity of High Melting Point Polyamides" (Adhesives Age, November 1986, pp. 24-29) discusses polyamide-type hot melt adhesives such as those prepared from hexamethylene diamine, adipic acid, azelaic acid or dimer acids.
Iwabuchi et al. in a paper entitled "Preparation of Regularly Sequenced Polyamides with Definite Numbers of Oxyethylene Units and Their Application as Phase Transfer Catalysts" (Makromol. Chem., Vol. 184, pp. 535-543 (1983)) disclose polyamides having oligo(oxyethylene) segments prepared from alpha-(2-aminoethyl)-omega-aminooligo(oxyethylenes) and dicarboxylic acid chlorides.